One the of the great advances in medical technology in recent years is the development of automated equipment for performing comprehensive analyses of blood samples to give readings of factors identified as red cell count, white cell count, hemoglobin, hematocrit, mean cell volume, mean cell hemoglobin and mean cell hemoglobin concentration. An automated hematology analyzer aspirates a specimen of blood from a sample container, performs the required tests, prints out the test results, and flushes the equipment in preparation for the next specimen, in a time interval less than one minute.
Samples of patient's blood are provided in 31/2 ml sample containers having rubber stopper closures. Specimen input to the analyzer is both "open" and manual, that is, a technician must take a previously shaken sample container (or must shake the container a predetermined amount), open the container by removing the stopper, immerse the aspirator tip of the analyzer into the sample, and actuate the analyzer. After the specimen input has been completed, the container must be restoppered and disposed of, and any liquid adhering to the outside of the aspirator tip must be removed.
Because the sample container must be opened and manually introduced into the system, laboratory personnel is exposed to a potentially dangerous environment.
All laboratory specimens are regarded as hazardous. Pathogenic microorganisms are readily spread to laboratory personnel by direct contact. With blood samples there is particularly concern over exposure to serum hepatitis. The open input of blood specimens to automated systems as described above results in exposure of technicians to contact with the blood dripping from the aspirator tip on the equipment, as well as to residual blood in the container and on the rubber stopper.